Loading machine



July 17, 1951 J. B. MODADE LOADING MACHINE l2 Sheets-Sheet 1 OriginalFiled Aug. 8. 1945 J. B. M DADE LOADING MACHINE July 1 7, .1951

12 Sheets-Sheet 2 Original Filed Aug. 8, 1945 J. B. M DADE'.

LOADING MACHINE July 17, 1951 Original Filed Aug. 8, 1945 N WM v NZ MnNW/V/VN/ WWW Z916 J. B. M DADE LOADING MACHINE July 17, 1951 12Sheets-Sheet 4 Original Filed Aug. 8, 1945 J. B. M DADE LOADING MACHINEJuly 17, 1951 12 Sheets-Sheet 5 Original Filed Aug. 8. 1945 .lufly 17,W51. J. B. MCDADE LOADING MACHINE Original Filed Aug. 8, 1945 12Sheets-Sheet 6 Ja'kmB Maj 1&7.

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J. B. M DADE LOADING MACHINE July 17; 1951 a N M 4 5 w SN 5 9w 51 @H w 2m F g 2 a I E m NH 1 Original Filed Aug. 8. 1945 J. B. M DADE LOADINGMACHINE July 17, 1951 12 Sheets-Sheet 8 J. B. M DADE LOADING MACHINEJuly 17, 1951 .lKShii 9 Original Filed Aug. 8. 1945 J. B. M DADE LOADINGMACHINE July 17, 1951 12 Sheets-Sheet 10 Original Filed Aug. 8. 1945July 17, 1951 J c Afi Re. 23,392

LOADING MACHINE Original Filed Aug. 8. 1945 12 Sheets-Sheet 11 J. B.MODADE LOADING MACHINE 12 Sheets-Sheet l2 Original Filed Aug. 8, 1945Reissue-d July 17, 1951 LOADING MACHINE John B. McDade, Scranton, Pa.Original No. 2,441,581, dated May 18, 1948, Serial No. 609,551, Augusta, 1945.

Application for reissue May 17, 1949, Serial No. 93,801

50 Claims.

My invention relates to a loader for coal or other material.

The main purpose of my invention is to make available the coal of anarrow vein,

A further purpose is to load a shovel by engagement of a gear connectedto it with a motionless rack and to stop or release the rack by a presetautomatic lock.

; A further purpose is to provide a loading head which can be engagedwith the cut pile of coal by direct thrust from the same source ofenergy and in which continued thrust from the same source of energycarries the shovel forwardly through the pile of coal and upwardly tofill and lock the shovel in upward filled position, ready forwithdrawal.

' A further-purpose is to project a scoop or shovel from a positionoutside a narrow vein of coal into a pile of coal to be loaded and atthe same stroke, by the equivalent of a hammer blow, to push the scoopthrough the pile and turn it to an upright, filled position.

' A further purpose is to project a runner-supported scoop or shovelbeneath the coal to be loaded, to load it and to withdraw it, instraight lines, while shifting the support from runners of one height torunners of a different height and turning the scoop or shovel upwardlyto fill it,

and to counterbalance the weight by the increasing weight of the rear ofthe operating mechanism until the latter overbalances the shovel and itsload and the shovel can be swung about an outside axis.

A further purpose is to drive a shovel and cooperating head forward toany predetermined position, to stop the head in this position where itcan engage the pile of coal to best advantage, to continue to drive theshovel forwardly and by cooperation with the head upwardly to fill theshovel and to withdraw the filled shovel for discharge and for asucceeding filling operation, all by direct plunger movement.

A further purpose is to drive a shovel or scoop forward into the coal byan hydraulic ram generally limited in its forwardmovement by the itsloading position while resting it upon the floor on runners, to turn andfill the shovel while shifting its weight to runners of a shorterradius, to retract the loaded shovel part way while resting upon thelower runners and to shift the center of gravity of the boom, shovel andcontent so that the shovel is lifted from the floor for'the final partof the retraction.

A further purpose is to provide an hydraulically driven shovel with stopmechanism carrying a turning rack, with adjustable means for determiningthe stopping points at which the rack may be made efiective and asegment gear carried by the shovel engaging with the rack to turn theshovel up through the pile of material loaded, if and when the rack isstopped in its forward movement.

Further purposes will appear in the specifications and in the claims.

I have preferred to illustrate my invention by a few only of the formsin which it may appear, selecting forms which are practical andeffective and which at the same time well illustrate the invention,

Figure l is a top plan view of a hand controlled form, sectioned on somesuch line as II of Figure 2 to show the plunger and cylinder.

Figure 2 is a side elevation, largely in longitudinal section upon line2-2 of Figure 1.

Figure 2 is a fragmentary side elevation of a portion of Figure 2 butillustrating a modification.

Figure 2 is a fragmentary side elevation of matter shown in Figure 2.

Figure 3 is a longitudinal section corresponding generally with line 33of Figure 2. The jack is partly broken away.

Figure 4 is a side elevation taken generally upon line 44 of Figure 2,and looking from the rear in the direction of the arrow toward theshovel. Figure 5 is a perspective view from the rear showing the 'mainoperating mechanism, but omitting such parts as the motors, pump andtank.

Figure 6 is a fragmentary perspective view.

partly in section, looking from the front and toward the rear, showingsome of the parts in Figure 5. The side supporting rods, shovel andother parts are omitted.

Figures '7, 8 and 9 are perspective views showing the gathering assemblyin different positions, including in different figures the selector barsby which bodily travel of the shovel is stopped and operating mechanismby which plunger opperation is converted into progressive shovel turningmovement as it fills to the lifted position of Figure 9. Figure 7 omitsthe shovel.

Figure 10 is an exaggerated perspective view illustrating the forwardtranslation, and rotary movement of the shovel in moving from empty tofilled position.

Figure 11 is a fragmentary top plan view, to enlarged scale, of gearingof the character of that seen in Figure 5.

Figure 12 is a fragmentary side elevation, omitting some of the selectormechanism, of the struc-. ture seen in Figures '7- to 10, showing. infull and in dotted lines, respectively, the opposite tilting positionsof the loader tilting about its. horizontal axis.

' Figure 13 is a perspective of a loader in rear position with theshovel lifted and turned and the parts tilted downwardly at the back.

Figure 14 is a fragmentary perspective showing the rear of the shovel inraised position.

Fi ures 15 and 1 6 are a top plan view and a side; elevationrespectively, to a reduced scale and in large measure diagrammatic,showing solenoid actuation on an hydraulic control, operating theplungerin reverse directions.

Figure 17 is a fragmentary side. elevation of a modified form of bearingfor the gathering assembly.

Figure 18 is a side elevation of a modified form of, shovel and itsmodified operating mechanism.

Figure 19 is a top plan view of the mechanism seen; in Figure 18.

Figure 19 is a top plan view similar to Figure 19 but. showing furtherdetailed mechanism, on the rear plate.

Figure 20 is a'front view of a shovel-carrying front :circssheadofmodified form with shovel in dot and dash lines.

Figure. 2 1; is a fragmentary side elevation showing the same crossheadas Figure 20.

Figure 22 is an end elevation of the right hand end: of;Figure' l9f,themechanism in the distance being omitted and the lock being shown asengagingaratchet.

Figures 23, 24 and 25 are perspectiveviews showing, structure ofmodified shovels.

Figure 26 is a fragmentary longitudinal section of acheck rod showingspecial latching notches.

Figures 27, 28' and 29 are fragmentary side elevations showing amodified form. of lever mechanismser'ving-the purpose of the rack andsegment gear.

In the? drawings similar numerals indicate like parts.

The. coal is .blasted at the face of the seam and fallson the floor of:the chamber from which it is gathered and removed. The present inventionis-dealing' with very narrow seams with the: result that the gatheringmechanism must bekept-extremely low. Hand shovelling conditions aresimulated and the filling of the shovel is accomplished by, aprogressive forward movement which :at the end of its stroke turns theshovel up through the pile.

A nyvdimensions givenxin this discussion must' be considered as examplesonly since conditions will vary greatly in different locations dependingupon many factors, among which are the thickness of the vein, thecharacter of the overburden, the availability of haulageways in whichmine cars can be operated, etc., and the dimensions will be affected bysuch differences.

. In Figure l of the drawing, one of my loaders shown in a chamber,-with a conveyor along the side of the loader and of a conveyor type wellknown in the mining art, namely, a Shaker ating valvemerely; fordistributingthe fluid from conveyor, made up of pans fastened to eachother of a type in which the shaking of the conveyor provides thelongitudinal feed of the conveyor along the conveyor length. Pans areadded to extend the length.

The loader The anchorage When-the loadenhas been placed in the posi--tion fromwhich itisintended to operate, it must be anchored very firmlyin order that its operation may be reliable and forceful and that theshaftseabout which the loader swings horizontally and tilts verticallymay be properly supported. I

Because thefloor of-the. chamber in which the loader is :to operateisnecessarily uneven, it is desirable that the base Ill-cover alarge.area. Itis anchored in position by a jack 43 welded to the base andwhose upper end terminates in a socket 52 within which rests a nut 53.The interior nut thread 54. engages the thread 55 of the hardenedjackpoint 56. The nut is rotated by a hand wheel 51- and. the threadmay bekept from rotating in any way of the many known.

The horizontal swinging movement ThGn-tlilhtfl'blilE supports the entiretilting assembly and -is mounted to rotate about the jack. for.convenience considered as. in horizontal planes. The. turntable; as seenin Figure 1, supports the gathering (vertically tilting) assembly ontoneside-of. the jackposition and a power plant for the gatheringaassemblyon the opposite side thereof, see-placed for convenience merelyinbalancing, The; .operatingnmchanism' for the gathering. assemblycomprises 'a motor 58, a pump 59',tank'-6ll for the hydraulicfluid-considered' hereas oil, oil intake 6| for the pump, fluid comm:82, connection": 63 from the pump to the control inlet. 64:- and outlet65 from the control. tothe hydraulic cylinder 66 and" return 67:fromathe control to:, the oil tank.

The; hydraulic control mechanism is an operthe ump 1110i and; from thehydraulic cylinder. It and its; solenoid controlare: well-known in theart. The valve can beoperated alternatively by the solenoidsv 68; 59,.through electrical switches 10 located at any suitable point or canbe-operated locally: by: anyrsuita-ble fluid connections from a handlever-,1 Y

In-order;.to=accommodate tilting'of the gathering: yassemblma the fluidconnections are made W flexible. The turntable is not merely free toturn but is turned by an electric motor I2 and suitable connections. Themotor may be supported above or below the turntable as preferred but inthe, illustration is above the table. Upon the motor shaft I3 is locateda pulley I4 connected by belt 15 with a pulley 16 below the turntable.The pulley 18 rotates shaft 'I'I carrying worm 18 engaging w ith wormgear I9 upon shaft 88 supported from the turntable. The shaft 88 carriesa gear 8| which meshes with a fixed circular rack 82, so that theturntable is rotated with respect to its support. Mechanism of thecharacter shown in Figures 1 and 2 is shown in a separate view in Figure11. There are so many ways of rotating the turntable that this issuggested merely as one operative way of performing the function.

Tilting of the gathering assembly Upon the turntable at any pointsuitable to balance the power plant are located ears 83, 84 whichsupport sleeve 85, turning on a pin 86 about which pin the gatheringassembly is capable of tilting. This tilting action is preferably leftwholly to gravity. The movement of the working parts forward and backthrows the center of gravityto the front or the rear, as the case maybe, of a vertical line through the pin 88 and causes the tilting. Exceptas it may be desirable to control by a lock, the tilting about the pinwill be dependent wholly upon shifting of the center of gravity due toextension or retraction of the plunger and to the shovel projected andretracted by it.

In all of the figures, the tilting assembly is free to tilt incounterclockwise direction, as viewed in Figure 2, at all times when themoment of the weight and distance to the left of the pivot pin isgreater than the moment of the weight and distance to the right of thispin in the figure. However, it is desirable for certain purposes toprevent the tilting assembly from turning in clockwise direction inFigure 2 as soon as the moment of weight and distance at the rightexceeds the moment of weight and distance at the left; and for thispurpose a lock is shown.

In Figure 2 a lock 8'! in the form of a pendulum arm is supported from apivot 88 on the gathering assembly 46 rearwardly of pivot pin 86 and isso balanced that the arm will tend to swing in counterclockwisedirection, so that the latch 89 will rest under keeper 98. It is heldthere by spring 9|, alternative to gravity operation and tends to remainunder the keeper, preventing the assembly from tilting in clockwisedirection. This swinging pendulum latch can be released by hand as bycord 92 (Figure 2*) or can be controlled by solenoid 93 and electriccircuit 94, controlled by switch 94 (Figure 2). The solenoid bar 95 islight enough to be thrown freely to pendulum locking position when thecurrent is not turned on at the solenoid.

Alternative to the gravity tilting of the gathering assembly by shift ofcenter of gravity from front to back or back to front with respect tothe tilting axis, the tilting may be accomplished by various othermechanical means such as the hydraulic jack shown in Fig. 2

The cylinder 96 and the plunger 91 of the jack are suitably connectedwith the turntable 45 and the tilting assembly so that the jack caneither push or pull, as may be desired. It is supplied with liquid,under pressure at either end, as at 6 98, 98' and the same connectionthrough the valve will be used for exhaust at the other end.

Driving and supporting mechanism for the gathering assembly The plate99, which is secured to the sleeve in any suitable way for tiltingmovement about pin 86 provides a support for the entire tiltingassembly.

Rigidly secured on the longitudinal center line of plate 99 is thehydraulic plunger cylinder 86, and to each side thereof, bearings I00are provided for supporting and guiding side rods IOI, which slidefreely through the bearings and which along with piston or plunger I05,are rigidly attached at their front ends to a front supporting crossheadI86, comprising spaced side plates I68, I89 secured to and extendingvertically from the transverse front and back crosshead plates I07, I08,and at the rear of the rods to a rear plate I09.

Means of attachment of the side rods and of the front end of the plungerare shown and are necessary, but their character is wholly immaterial.

Conveniently above the side rods is located a check rod IID, which issupported against 1a;- eral movement in the rear plate but is free toslide through a bearing I i, supported by the rear plate.

Check rod IIII carries a check finger H8 (Figure 13) mounted upon acollar I I8 movable along the length of the check rod and adapted to beset in any suitable position along the rod by set screw I29 (Figures 12and 13).

The purpose of a check finger is to engage with stops 58 which projectinto its line of travel from 'the relatively fixed support, for thepurpose of stopping movement of a check rod at any of a number ofpredetermined positions in order that a shovel may begin operation at apoint selected as a stop. Where bulldozing is intended, the finger isset so that it will not engage a stop.

Upon the crosshead of the tilting assembly is mounted a supporting andstabilizing bearing I I5 through which the check rod slides. Adjacent tothis stabilizing bearing there is mounted a ratchet wheel I25 fixedagainst longitudinal movement along the check rod and supporting checkbars which form stops to be engaged by the check finger. In the earlierform the ratchet wheel physically supports the check bars so that thewheel and the bars supported by it can be turned transversely to thelengths of the bars about the check rod and can be latched in any of theselected positions.

The latch I 25 is spring mounted to engage Within the ratchet recessesin the exterior of the wheel and the heel I2! of the latch engages witha collar I28 (Figure 13) on the wheel to hold the ratchet wheel frommoving in one direction, longitudinal movements in the other directionbeing prevented by engagement of the end of the wheel with the angleplate I29 (Figure 6), whose flange I39 is bolted to the front of astuffing box I3l, used to seal against the operating plunger.

By turning the collar and check finger circumferentially about the checkrod and fastening it in the position to which it has been'turned, thecheck finger can be set so that its path of movement will cause it toengage with any stop selected, or to be free from engagement with anystop.

The forward end of the check rod H9 carries a rack II, 2 (Figure '1)which is normally unrestrained 'and' free to move longitudinally 'withrespect "to the frontcrossh'ead. The rack is restrained against upwardmovement by hearing I I 3 and meshes with a segmental gear I I6 which isrigid with the shovel, these means, co operating to translate and rotatethe shovel as herematte expla ned- The shovel In he us o t e WO ho e itin e e qin lu e a ainer c able of eri from a pile whether the containermight be more naturally referred to as a bucket or as a scoop, forexampl or nQt e a e pres nt n ention is considered to be applicablegenerally to all suchtypes of containers having openings into which thematerial is gathered as the shovel is pushed forwardly. It is theintention therefore to give the shovel a generic meaning.

Whatever the type of shovel, it is the intention to secure it rigidly towhat is effectively a gear IIS and to mount the whole unit about an axisin a pin II'! or other support so that the gear will mesh with the rackH2 and shift the racl; if the gear rotate without translation but tocause rotation of the gear and of the shovel if the gear travellengthwise of the rack while meshing with it. The pin will thereforeoccupy different positions with translation along the length'of the rackas indicated at the. initial position Hi5, and two succeeding positionsI88 and I6! which correspond with the dotted positions shown for thefront of the shovel in Figure 10. Because the construction does notrequire that the entire circumference of the gear be used, it has beenreferred to somewhat as a segment.

The two ends of the pin III are supported in plates I68 and IE9 (Figure7), and the connection of the shovel to the gear is made through platesI10 and I'll which are Welded to an adja cent portion 345 of the shovel(Fig. 7)

Two forms of shovel are shown herein. The first form of the shovel has alatched rear gate which becomes the bottom when the shovel is turnedupwardly in filling. This latched rear gate I33 is shown in Figures 5,S, 9 and 14.

It is hinged at I34 and is fastened in any suitable Way as by latch I35pivoted at I35 and spring-pressed at I31. The latch can be released byhand by pulling cord I38 (Figure 1. or it can be released from a moredistant point, as by a solenoid. The character of thelatching andunlatching mechanism does not alter the effective character of therelease when the latch has farther from the supporting pin IiI than therear ends I42 (Figure 12) for a double purpose. First, so that inturning upwardly through the pile to be gathered, the shovels supportingarm with the shovel may be allowed to settle slightly toward the floorof the chamber as it fills, in order that there may be not quite so muchwork required in lifting the material from the pile, and second, so thatwhen the arm is retracted with the load to a point where the load isto'be swung horizontally preparatory to discharge, shift of center ofgravity of the combined arm and sh v e the t tin axis or. fo ible il ingof the arm about the a r-is will be more effective in spacing the shovelfrom the'fioorfof the chamber reliably than would otherwise be the caseand the arm carryingthe' sh'ovelfmay the 5 forebeshifted'horizontally'so' as to bring'it n line anguiany with theposition at which the shovel is tobe emptied. 1 The front I43 oftheshovel above the runners, the sides I44, and the rear I45 includingthereai gate enclose a shovel contentwhich is verveasuy retracted,turned and emptied. In Figures 5, 7, 8, 9, 10 and 12, one form of latchis shown by which the shovel can be held in "its raised position afterit has been swung up through the pile of material being loaded. In thislatch, a spring arm I58 is supported in any suitable way from theshovel, as by platel5fin ord present latch fingers I52 in a positionresiliently to engage the rear surfaces I54 of keepers"l'53.' The frontand top surfaces I55 of the keepers spring the'finge'rs upwardly duringthe upward swing of the shovel and the fingers snap to position back ofthe keepers. With this particular form of latch, automatic mechanicalrelease is provided in the form of horns I56 and I51, secured to eitherside of plate I29 and carrying] at their outer ends cam faces I58 to beengaged by the fingers, when the shovel is retracted fully. When thislatch is used it is the intention to stop retraction of the'shovel ashort distance from the rear of the shovel stroke, retracting most ofthe distance but not the full stroke. After the shovel has been swunginto the proper angular position for emptying, extended to the positionat which its content: is to be discharged and emptied, the shovel isthen fully retracted to release the latches and permit the shovel tofall downwardly from its loaded position to the position of Figures 10and 12. The final retraction can'take place at any time between theemptying of the shovel and the beginning, of a new cycle. Releasing ofthe latches may be, therefore, effected during the time that theturntable is being swunghorizoh tally so as to bring the gatheringassembly into proper angular position to start another cyclel" It willbe clear that the' construction shown is a build-up from elementalmaterials'and that the parts shown can be supplied by castings, forgins; etc, to unite in one piece initially parts which are indicated asmade in several parts and welded or otherwise fastened together. Thisapplies particularly to'the buiIdF'up of the cross heads, tothe'su'p-ports for the 'gear' and shovel, and to the way in which theselector bars, ratchet wheel and other parts are assembled.

Operation The operation may be well understood by reference to Figs. 10and 12. In these figures there are shown in solid lines the initialposition of the parts before gathering begins and indotted lines thepositions after gathering.

The supporting mechanism" for the, tilting as: sembly and the jack andall of the power-plant structure have been omitted so that We aredealing with the bare assembly parts. The positions of the parts assumethat the lock against forwardly and downwardly tilting hasbeen released.

Fluid under pressure has been'supplied tothe plunger cylinder and theplunger or thruster has started forward and has reached a point at whichthe torque due to weights of-the front parts inudins h Q hea h s ovel.he side guide rods the chec rod wh ch .li forwardof the tilting axishave overbalanced the torque due to weights of the remainder of theparts of the plunger, side guide rods and check rod as well as thecylinder behind the tilting axisso that in the absence of lockingagainst tilting, automatic tilting forwardly and downwardly has takenplace. Since the shovel is emptied and in position to begin gathering,the shovel has settled down upon the longer radius of its runners withits teeth in position to engage the pile to be gathered.

Remembering that the side supporting and guiding rods and the plunger(thrustor) are connected to the front crosshead, that the gear rigidwith the shovel is held against rotation by the friction against thelower part of the shovel and that the rigidity of the position of thegear likewise fixes the position of the rack with respect to the otherrods, it is clear that the check red, as well as the other rods named,will travel forward with the shovel and at the same speed as thecrosshead. This condition of relative speed and maintenance of initialpositions of some of the rods with respect to the others continues untilthe check rod finger meets and is stopped by that selector bar whosestopped position corresponds with the location of the pile to behandled.

The selector bars are for the most part not shown in Figure 12, but aparticular selector will have been chosen and will have been turned intothe path of movement of the check rod finger (applying to the first formwhere the selector bars swing about the check rod).

When the check rod finger engages a selector,

the check rod is stopped and correspondingly the rack upon the end ofthe chuck rod is stopped; but the plunger (thrustor) continues to moveand carry with it the front crosshead along with the side guiding andsupporting rods which are rigidly connected with it.

As suggested, that selector will have been chosen which stops thecheckrod and rack just when the shovel is about to attack the pile ofmaterial to be gathered and loaded; with the result that the gear in thefront crosshead begins to travel along the rack, as indicated by I65,I66 and I61 of Fig. 10, and the teeth of the shovel rigidly attached tothe gear begin to revolve forwardly and upwardly at the very beginningof the approach of the contact of the shovel with the pile.

The upward turning movement of the shovel is continuous with its forwardthrust and is so rapid that perhaps the shovel should be considered aswhirled. The effect is as of a hammer blow. When it has been whirled tofilled position, as elsewhere more fully discussed, it is necessary thatit be held in an upturned position during the withdrawal of the shovelso that the attempt to withdraw does not reverse the whirling of theshovel and spill the contents. For this reason a latch is required tohold the shovel in its upturned position; and this latch also must becapable of convenient release after it has been emptied in order thatthe empty shovel may assume its proper horizontal position for thebeginning of a new cycle.

The side guiding and supporting rods llll travel not only with theplunger and with the front crosshead, but for the most of the stroke ofthe plunger travel also with the check rod, the four forming aparallelogram. When the check rod is stopped, the guiding and supportingside rods, the plunger, the front crosshead and the rear plate I09continue their movement and 10 may be considered as telescoping thecheck rod.

The side rods and the plunger as well as the front crosshead, and to aless extent the rear crosshead, greatly increase the inertia of themoving parts which continue to move after the check rod has stopped.They advance the rack gear along the rack, and as a continuous stroke,not only move the shovel forwardly with the open bucket facing to thefront, but turn the bucket upwardly to fill it and to latch the bucketin its upper position with the bucket opening directed upwardly, gettingfull advantage from the effective hammer blow to which these parts somuch contribute.

It will be noted that the identical action of the shovel takes placebeginning when the check rod is stopped, no matter at what position thestoppage of the check rod takes place.

Various ways are effective to stop the forward movement of the segmentgear along the length of the rack, of which two only-are shown.

In Figure '7, a point I12 on the shovel adaptor is arrangedto strikeagainst a point I13, upon the supporting plates by which the pivot pinis mounted so that the revolution of the shovel will be stopped at anyangle provided, represented by the engagement of these two positions. a

It will thus be apparent that the shovel is unloaded at the start andhas dropped in clockwise direction from its loaded position to theinitially unloaded position seen in Figure 12.

During the loading operation the shovel whirls upwardly causing thesupport of the shovel to be shifted from the front Hll of the runners tothe rear M2 of the runners, resulting in a slight clockwise tilting ofthe assembly. 1 Because of the shorter radii of the rear parts of therunners as compared with the radii of the front parts of the runners,this reduction in the height of the shovel considered as an entiretyreduces the amount of energy required to drive the shovel up through thepile of material.

After the shovel has been latched in its raised, filled position, as inFigure 2, the tilting assembly can be retracted hydraulically by theplunger without danger of the shovel discharging prematurely through itsfront opening by gravity reversals of the position of the shovel,

During the retraction and until the assembly tilts by gravity incounter-clockwise direction, as viewed in Figure 2, the shovel ridesupon the floor of the chamber on the rear portion of its runners so thatboth the shorter radii at the rear portions and the counter-clockwisetilting of the assembly due to gravity as it approaches the tilting axiscontribute to lifting of the shovel from the floor. As a result when theshovel has lifted, the turntable can be rotated to swing the shovel to anew direction of movement at which the shovel can again be extended foremptying purpose. Itwill be noted that the retraction of the shovelbefore this re-extension for emptying will not be far enough for thelatches upon the shovel to be released by the cam surfaces uponthehorns; so that the shovel will be maintained in lifted position and fulluntil it can be extended in the new direction for emptying through therear gate.

The catch of the rear gate may be opened electrically or by pulling thecord (Fig. 12) or in any suitable manner.

It will be remembered that from the time that the assembly has beenretracted with the shovel full, the tilting mechanism is locked againstextended gravity tilting forwardly and downwardly so that the extensionof the assembly in the new l l direction for emptying purposes does notcausetilting even though the center of gravity passes the axis. Theshovel may be emptied into a pan of a conveyor or in any suitable place.

After the shovel has been emptiedit'is swung to a position for thebeginning of a new cycle and is also tilted in clockwise direction (asviewed in'Flgu-re 2), the former being accompanied by the turntablemovement and the latter by releasing the latch holding the shovel up.This latch can be released by pulling the cord, for example, or byelectrical means, and the two operations can be performed in eitherorder or concurrently. Before the second cycle is started or earlierin'the movement of the thrustor before the second cycle, the thrustormust be released sothat it can tilt forwardly.

j The conveyor I 80, shown in Figure 1, is intended to be generic inthat it may be any conveyor which can operate within the chamber andupon which the content of the shovel can be emptied. The structure ofconveyor shown corresponds with a well known type of shaker conveyor, inwhich shaker conveyor pans Il3| are fastened together at I82 in sectionsas the chamber is exhanded and in which the longitudinal shaking of theconveyor feeds the material mined toward the master conveyor or the carby which this material is ultimately carried out by the haulageways.

Some of the fundamental advantages of the present invention are that itgathers the coal into a; suitable shovel or scoop by direct thrust,concurrently turns the shovel up through the pile of coal while theshovel is advancing so as to fill the shovel fully and holds the coalsecurely within the shovel. 'Because the thrust is direct, the mechanismcan be kept extremely low so as to operate to its best advantage acrossthe breast within a chamber formed by removal of the coal from a thinseam.

This greatly cheapens the loading operation. In contrast to this, atpresent the work must be done by hand, or rock must be removed inaddition to the coal for the purpose only of giving room for a high andcumbersome machine.

' My machine in ractice telescopes to a fraction of its total operatinglength, adjusts to start its gathering operation in any positionthroughout its range and finishes its gathering movement by a hammerblow'which lifts the shovel up through the pile to complete the fillingof the shovel.

In'Figure 17, a slightlydifferent construction of the bearing for thetilting assembly is shown at I95; as compared with that in Figure5,"using a standard form of ball bearing to ensure as low friction aspossible in the tilting support. 7 In the Same figure a slightlydifferent angle plate is used and the bearing I00 differs slightly fromthe bearing shown in other figures.

7A different form of shovel is shown in Figures 18, 19, 23, 24 and25,'which for many uses represents adistinct advantage over the shovelof the previous figures. This second form is described and claimed in a;copending divisional application for Loading machine, filed by me onNovember 14, 1945, Serial No. 628,592, now Patent No. 2,441,582, filedNovember 14, 1945. It is the intention not to claim the detail of thisform here- This later form of shovel is front emptying may be emptied atany point along its travel; and may be positioned at the same point fora new cycle without going back to the retracted position to release thelatch holding the shovel up in loaded position. It tilts about an axiswithin the body of 12 the shovel, as distinguished fromtilting about anaxis outside of the shovel and has a. different form of latch which, forsome purposes, has special advantages.

The runners are differently placed and are in the form of what might bedescribed rather as shoes than as runners. The shoes 243 are shown inFig. 18 only. For some uses, neither runners nor shoes-will be neededand both have been omitted from the remainder of the figures.

The shovel of the later figures has much greater capacity than that ofthe best forms of the shovels earlier illustrated. The later form ofshovel uses torsional springs.

Because the shovel discharges from the front and it is desirable not totilt it reversely to an excessive extent, the front wall 200 slopesdownwardly and inwardly to a considerable extent, as shown in Figure 18.

Since the positionsof the shovel correspond to different extents ofprojection of the check rod H0 at. the rear end 20! in the tiltingassembly and because the check rod "is accessible at thispoint,.advantage is taken of the opportunity to latch the shovel inrested position by latching the position of the check rod at its rearand. exposure. This is shown in Figures 19, 19, 22 and 26 and will bedescribed later.

However, with this character of latch and a front emptying shovel, theshovel not only can be emptied at any point in the length of its travelbut can be" swung to its initial counterclockwise position, as comparedwith Figure 18, ready to start a new cycle. In connection with thelatching construction of the check rod in Figure 26, the shovelfurthermore is capable of latching with partial filling movement only ofthe shovel because of the presence of torsional Springs 202, also to'bedescribed at a later point.

With the use of the torsional springs and the latching mechanismengaging a ratchet latching keeper, it will be possible to completelyempty the shovel whether the shovel be initially fully filled or-butpartly filled, so that a new cycle may be started at any point ofretraction at which it is desired to empty the shovel.

The later illustrated shovels have the same form of tilting of theshovel by progressive driving' movement'of the plunger as the earlierforms but difier in the location of the tilting axis by reentrantlycontouring the rear of the shovel. In the central part of its length arecess 294 (Figure 23) is provided between wall 205. At opposite ends ofthe shovel, in line with the recesses, pockets 206 are located, not onlygiving additional capacity for'material loaded but also placing part ofthe coal in these pockets in position to partially counterbalance thecoal in the upper front of the shovel.

Within the recess and between the pockets, I locate the segment l [6effective as a gear and because of the difliculty in mounting it upon apin, I pass a shaft 208 through the length of the shovel as a supportfor the gear. The gear engages a rack upon check rod llil, which checkrod maybe stopped by a check finger. Though the check rod constructionand the selector bars are different in the form shown in Figure 18, theoperation is the same, namely that the check finger or the selector barsmay be turned one with respect to the other about the check rod axis sothat selectively the check fingers may find any preferred check rodwithin their path of movement or the check rod may be so located as notto meet any of the selector bars and therefore as not to stop movementof the rack and not to cause revolution of the shovel.

The last use, freeing the check finger from selector bar engagement,will be used for special purposes where bulldozing or raking is intendedand a special tool is used, or where a shovel, if used, is not intendedto be revolved.

In the form shown in Figures 18 and 19, the

. shoulder, with which the selector finger is incheck rod H0, in orderto secure additional strength, is made up of a composite rod comprisingan outer tubing 239 within which operates a longitudinally extending,re-enforcing rod 218. The finger H8 in this form is a' bar 2H which isfastened in the re-enforcing rod and extends transversely throughopenings in the tube so that the edges of the bar are longitudinallysupported by the walls of these openings.

The check finger, however, operates in precisely the same manner as doesthe check finger I I8 in the other views.

The check rod of Figures 18 and 19 is intended to cooperate with ashoulder sleeve 2 I2 which surrounds the check rod and which is cut awayso as to provide progressively at different lengths along the check rod,shoulders 2 I3, H3, 2 I3 etc., against which-the check finger is adaptedto engage selectively according to the length of travel of the check rodintended, before the shovel reaches the position at which it is to beloaded.

,Since the selector bar sleeve may be mounted about the tubing of thecomposite check rod, it can be turned freely about this tubing topresent different shoulders within the path of movement of the checkfinger I [8, which check finger, therefore, need not be rotated.Furthermore, the selector bar sleeve can be turned to a point at whichthe check finger will not engage any shoulder, permitting travel of thecheck rod along slot 2 I4 without stoppage and therefore without anyrelative lengthwise movement between the rack and the gear. The slot 2Mmay be cut all the way through or be out far enough through only so thatthere will be no stoppage of movement of the check finger H8. If theslot be cut all the way through, the tubing may be selected of such sizeas to tend to spring shut about the intermediate tubing between it andthe interior rod, so as to permit the shouldered, outer tube to beretained in adjusted positions by the friction upon the intermediatetube even if the slot 21 1 be not cut clear through. Advantage is takenof circumferential spring of a cut tube the size of the outer tubecarrying the shoulders which may be such that it will just hug theintermediate tube with sufficient friction so as to permit longitudinalmovement of the check rod throu h it to cause engagement of the checkfinger with the shoulders while having enough friction to preventcircumferential movement between the outer and the intermediate tubes.The shouldered selector tube may be rotated by handle 215 to secure newpositions.

The third form of selector bar and check finger construction appears inFigure 26 where the check finger 215 is capable of being adjustedcircumferentially so as to cooperate in its longitudi" nal movement witheither selector bars of the type shown in the earlier figures or withselector shoulders of a type shown in Figure 18, but iii either eventwith the selector bars or shoulders anchored against circumferentialmovement that is rigidly fixed to some suitable support. The form inFigure 26 has the great advantage that it can be supplied with alatch-like indicator which will show the position of the particular baror tended to cooperate. Because this adjustment to difierent selectorbar positions must be made in a narrow space under cramped conditions,it is a great advantage to have the adjustment capable of being made atthe extreme rear of the thrustor and to have the advantage of anindicator at this extreme end by which the position of the check fingerwith respect to the bars or shoulders can be determined accurately.

A further advantage in the form of Figure 26 lies in the fact that ifthe mechanism is capable of being set by means located wholly at therear of the thrustor, a large part of the remainder of the mechanism canbe protected by a covering 2|! with considerable advantage in protectionof the mechanism.

In Figure 26 the check rod I0 may be tubular but unaltered in contourfrom the rack back to a point close to the position of the check fingerat which point all of the mechanism canbe 10'- cated. The intention isto provide a check finger 216 which can be adjusted circumferentiallyand whose adjustment can be indicated at the rear of the mechanism wherethe adjusting means is also located. i

In the construction shown, the tubular chec rod end is threaded at 2l8to receive a threaded stub 219 which should preferably screw into thethread of the tube tightly enough to remain in adjusted position, Thestub 219 is rigid with a check finger body 22H which carries the checkfinger 216.

if the stub 2H therefore, be screwed in or out of the thread in the mainpart of the tube, the angular position of the check finger will bechanged correspondingly. It is necessary only, therefore, to providemeans by which the body 220 may be turned to screw the stub 2H! rigidlyattached to it inwardly or outwardly to obtain the intended angularadjustment.

In the form shown, the body 220 is provided with a threaded stub 22l onthe opposite side of the body from stub 219. This threaded stub 22!,rigid with the body, is extended at 222 in order to carry a lever arm223 which is held in place upon it as shown by a set screw 224. Thethreaded stub HI and the extension in the form of shaft 222 issurrounded by a sleeve 225 which performs two functions. It is threadedupon the stub 22! to support rear ratchet recesses 225, within whichwill fit a spring detent 221 carried I by the adjusting handle 228, andthe detent face desirably carries any type of dial by which the angularposition may be determined from the end. 4

A further function of the sleeve 225 is that it is notched at 229 forengagement by a latch 230-not shown in Figure 26 but seen in Figure22-if latching of the full stroke only of the shovel is to be provided.On the other hand, if it be intended to latch the shovel in whateverpartly rotated position it may assume, this may be provided by ratchetednotches 23I (Figure 26) into any one of which the latch 23!] may fit,the movement of the selector rod pushing the ratchet faces past thelatch so that the latch will engage with that ratchet face farthest fromthe handle 228 reached by the rod as a result of the turning movement ofthe shovel and the reactive position of the gear in this position of theshovel upon the rack and therefore upon the check rod connected with therack. In this way, as the shovel turns in clockwise direction, as viewedin Figure 18, the latch will be pushed out successively by th differentratchet .faces shown from ratchet face 232 to ratchet face 233; and thelatch will rest in and hold at any of the intermediate locking faces234.

One form of latch capable of useeither with the single notch at 229 orwith the ratcheted notches at 23! is shown in Figures 19 and 22. In thisfigure, the actual latch which engages in the notch or notches islocated at one end of the lever 235, and is pivoted at 236. It is springpressed into engagement with the notch normally by a spring 231 and isreleased from this notch when the current is on the solenoid by link 238which is the right hand link in Figure 19 When the solenoid isenergized, its armature 239 is drawn inwardly in the figure with theresult that lever 248 (Figure 19 is turned about its pivot 24! so as topull the lever 238 upwardly in the direction of the arrow. The lever23:; is pivotally connected at 242 with the latch 23!] so that as thelink 238 is pulled upwardly in Figures 19 and 22, the latch is releasedfrom the notch in which it may be engaged and is held in releasedposition as long as current is continued through the solenoidal winding.

During the forward movement of the thrustor, the points 245 travel alongthe floor of the chamber and the front surface 200 lies substantiallyperpendicular to the floor of the chamber as seen in dotted lines inFigure 18.

During the retractive movementof the shovel when the shovel is in theposition seen in Figure 18, the weight of the shovel rests upon thesurface 241 of the shoes as it is pulled back by retraction of thethrustor. During this movement, the shovel is latched in the positionseen in Figures 18 and 19 by the latch described above, located at therear of the check rod and will come back to any desired distance, clearback to the innermost position of the thrustor unless the latch at therear of the check rod be released earlier;

While the emptying of the shovel normally takes place after at leastpartial retractive move- The shovel cannot be satisfactorily emptiedafter it has been filled or partly filled unless the shovel'end of thethrustor be tilted high enough to permit the shovel to fall back to aposition where the coal will slide out over the front of the shovelwhich now, by reason of its position, becomes the bottom of the shovel.For this reason, unless the thrustor has retracted to a point where ittilts by gravity, a jack or other tilting means must be used, of whichone form is shown in Figure 2 In normal use, the emptying of the shovelwill take placeafter the more or less complete retraction of thethrustor, and after the thrustor tilts upwardly at the shovel end.Releasing of the latch in this case permits the shovel to swing as apendulum back beyond the point at which it would ultimately hang, andsubsequently forward, repeating, until it stops. It thus moves fartherback than would be necessary for the content to slide down the frontwall and dis- 16 charge. As later more fully explained, this pendulumaction is assisted by torque springs.

In the position shown in Figure 18 it is not the intention that thepoints 245 must actually en,- gage the floor of the chamber. Instead,they are preferably slightly lifted so as to ride above the floor, thusriding over irregularities in the fioor.

This lifting of the points does not interfere with the shovel properlydigging under and into the pile of material to be gathered.

It is desirable to keep. the tilting assembly nearly horizontal for thereason that the long end with respect to the tilting axis, whether it bethe end at the rear or the shovel at the front, must belimited in itsmovement to avoid striking the roof or the floor.

In Figure 18, the shovel shoes protect against excessive elevation ofthe rear of the tilting assembly. The tilting must evidently becontrolled in both directions.

I have already described the locking of the tilting assembly in itsposition in which the shovel is lifted on retraction, requiring that inprojected discharge position the shovel be lifted far enough from thefioor for there to be room for discharge of the content. This is truewhether the shovel empty through the rear (at that time lowergate) orthrough the front of the shovel.

With either form, if the runners or shoes be omitted the shovel must beheld in elevated position during retraction.

With the second form of shovel, in the absence of shoes (Figures 23, 24,25) the swinging of the shovel forwardly and upwardly, as in Figure 18,would mean that the bottom of the shovel touches the floor of thechamber unless the tiltting assembly turns in counterclockwise directionabout its axis.

If the shoes be not used, it is desirable to maintain the shovel in thelifted position of Figure 18 during its entire retractive stroke inorder that the shovel may not engage the floor, which-would interferewith the horizontal swinging movement of the shovel to a new horizontalangular position along which the shovel is to be projected to the pointof discharge. In this structure, as in the earlier structures described,the tilting assembly on retraction will tilt automatically to lift theshovel somewhat from the floor as soon as the center of gravity of theassembly passes the tilting axis.

In Figure 17, blocks 25! are inserted between the turntable and thebearings through which the supporting and guiding rods slide forwardlyand rearwardly. These blocks support the front of the tilting assemblyso that, independently of the lock for the tilting mechanism, the shovelis maintained at a desiredheight. This height is selected as a height atwhich the tilting assembly will be approximately horizontal.

It has been found that when the blocks are used the shovel points-or thefront of the shovel close to the pointsshould just rest upon the floorof the chamber with the assembly tilted forwardly and downwardly. Theblocks used are regarded as pinch blocks because in action they arepinched between the tilting 'crosshead and the turntable.

The shovels shown in Figures 18, 19, 23, 24 and 25 can have considerablygreater capacity than those shown in the earlier figures because theswinging of these shovelsof Figures 18, 19, 23, 24 and 25 about an axispassing through part of the content makes it possible togather thecontent

